Effects of Fencing on Soil Physical and Chemical Properties of Spring-Autumn Grassland in Zhaosu Horse Ranch

Soil physical and chemical properties of fencing and non-fencing spring-autumn grassland in zhaosu horse ranch were investigated,the results showed that the soil bulk density decreased about 5.08% after the grassland was enclosured,and the surface soil changed significantly. The soil prosity increased about 2.39% after the grassland was enclosured,which was opposite to the trend of bulk density. The moisture content of soil was higher in enclosured grassland than that of non-enclosured grassland in mid-July and the trend decreased after late-July because of reduction of precipitation. The contents of soil organic matters and other total nutrients were higher in enclosured grassland in comparison with that in non-enclosrued grassland,however,the trend of contents of available nutrients was opposite,especially available N and K. The soil temperature in non-enclosured grassland was higher and varied greately in each layer than that in enclosured grassland,the variation of temperature in enclosured grassland was less,which provided good environment for growth of vegetation.